diff mbox

AutoFDO patch for trunk

Message ID CAO2gOZWLbyp7hiUaRv17t9BmiNL55LHb+b9p_t1GZnxmregAcA@mail.gmail.com
State New
Headers show

Commit Message

Dehao Chen Oct. 14, 2014, 9:05 p.m. UTC
On Tue, Oct 14, 2014 at 8:02 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
>> Index: gcc/cgraphclones.c
>> ===================================================================
>> --- gcc/cgraphclones.c        (revision 215826)
>> +++ gcc/cgraphclones.c        (working copy)
>> @@ -453,6 +453,11 @@
>>      }
>>    else
>>      count_scale = 0;
>> +  /* In AutoFDO, if edge count is larger than callee's entry block
>> +     count, we will not update the original callee because it may
>> +     mistakenly mark some hot function as cold.  */
>> +  if (flag_auto_profile && gcov_count >= count)
>> +    update_original = false;
>
> lets drop this from initial patch.

Done
>
>> Index: gcc/bb-reorder.c
>> ===================================================================
>> --- gcc/bb-reorder.c  (revision 215826)
>> +++ gcc/bb-reorder.c  (working copy)
>> @@ -1569,15 +1569,14 @@
>>    /* Mark which partition (hot/cold) each basic block belongs in.  */
>>    FOR_EACH_BB_FN (bb, cfun)
>>      {
>> -      bool cold_bb = false;
>> +      bool cold_bb = probably_never_executed_bb_p (cfun, bb);
>
> and this too
> (basically all the tweaks should IMO go in independently and ideally in
> a way that does not need flag_auto_profile test).

Done.

>> +/* Return true if BB contains indirect call.  */
>> +
>> +static bool
>> +has_indirect_call (basic_block bb)
>> +{
>> +  gimple_stmt_iterator gsi;
>> +
>> +  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
>> +    {
>> +      gimple stmt = gsi_stmt (gsi);
>> +      if (gimple_code (stmt) == GIMPLE_CALL
>> +       && (gimple_call_fn (stmt) == NULL
>> +           || TREE_CODE (gimple_call_fn (stmt)) != FUNCTION_DECL))
>
> You probably want to skip gimple_call_internal_p calls here.

Done

>> +
>> +/* From AutoFDO profiles, find values inside STMT for that we want to measure
>> +   histograms for indirect-call optimization.  */
>> +
>> +static void
>> +afdo_indirect_call (gimple_stmt_iterator *gsi, const icall_target_map &map,
>> +                 bool transform)
>> +{
>> +  gimple stmt = gsi_stmt (*gsi);
>> +  tree callee;
>> +
>> +  if (map.size() == 0 || gimple_code (stmt) != GIMPLE_CALL
>> +      || gimple_call_fndecl (stmt) != NULL_TREE)
>> +    return;
>> +
>> +  callee = gimple_call_fn (stmt);
>> +
>> +  histogram_value hist = gimple_alloc_histogram_value (
>> +      cfun, HIST_TYPE_INDIR_CALL, stmt, callee);
>> +  hist->n_counters = 3;
>> +  hist->hvalue.counters =  XNEWVEC (gcov_type, hist->n_counters);
>> +  gimple_add_histogram_value (cfun, stmt, hist);
>> +
>> +  gcov_type total = 0;
>> +  icall_target_map::const_iterator max_iter = map.end();
>> +
>> +  for (icall_target_map::const_iterator iter = map.begin();
>> +       iter != map.end(); ++iter)
>> +    {
>> +      total += iter->second;
>> +      if (max_iter == map.end() || max_iter->second < iter->second)
>> +     max_iter = iter;
>> +    }
>> +
>> +  hist->hvalue.counters[0] = (unsigned long long)
>> +      afdo_string_table->get_name (max_iter->first);
>> +  hist->hvalue.counters[1] = max_iter->second;
>> +  hist->hvalue.counters[2] = total;
>> +
>> +  if (!transform)
>> +    return;
>> +
>> +  if (gimple_ic_transform (gsi))
>> +    {
>> +      struct cgraph_edge *indirect_edge =
>> +       cgraph_node::get (current_function_decl)->get_edge (stmt);
>> +      struct cgraph_node *direct_call =
>> +       find_func_by_profile_id ((int)hist->hvalue.counters[0]);
>> +      if (DECL_STRUCT_FUNCTION (direct_call->decl) == NULL)
>> +     return;
>> +      struct cgraph_edge *new_edge =
>> +       indirect_edge->make_speculative (direct_call, 0, 0);
>> +      new_edge->redirect_call_stmt_to_callee ();
>> +      gimple_remove_histogram_value (cfun, stmt, hist);
>> +      inline_call (new_edge, true, NULL, NULL, false);
>> +      return;
>> +    }
>> +  return;
>
> Is it necessary to go via histogram and gimple_ic_transform here?  I would expect that all you
> need is to make the speculative edge and inline it. (bypassing the work of producing fake
> histogram value and calling igmple_ic_transofrm on it)
>
> Also it seems to me that you want to set direct_count nad frequency argument of
> make_speculative so the resulting function profile is not off.

This function is actually served for 2 purposes:

* before annotation, we need to mark histogram, promote and inline
* after annotation, we just need to mark, and let follow-up logic to
decide if it needs to promote and inline.

And you are right, for the "before annotation" case, we can simply
call "mark speculative" and "inline". But we still need the logic to
fake histogram for "after annotation" case. As a result, I unified two
cases into one function to reuse code as much as possible. Shall I
separate it into two functions instead?

>
> The rest of interfaces seems quite sane now.  Can you please look into
> using speculative edges directly instead of hooking into the vpt infrastructure
> and fixing the formatting issues of the new pass?

I'll work on the formatting issues now (need to learn the format first
;-). The attached patch is up-to-date except for formatting changes.
I'll upload the patch again once the format change is in.

Thanks,
Dehao

>
> I will try to make another pass over the actual streaming logic that I find bit difficult
> to read, but I quite trust you it does the right thing ;)
>
> Honza
diff mbox

Patch

Index: gcc/debug.h
===================================================================
--- gcc/debug.h	(revision 215826)
+++ gcc/debug.h	(working copy)
@@ -169,6 +169,7 @@ 
 extern const struct gcc_debug_hooks sdb_debug_hooks;
 extern const struct gcc_debug_hooks xcoff_debug_hooks;
 extern const struct gcc_debug_hooks dwarf2_debug_hooks;
+extern const struct gcc_debug_hooks auto_profile_debug_hooks;
 extern const struct gcc_debug_hooks vmsdbg_debug_hooks;
 
 /* Dwarf2 frame information.  */
Index: gcc/auto-profile.c
===================================================================
--- gcc/auto-profile.c	(revision 0)
+++ gcc/auto-profile.c	(revision 0)
@@ -0,0 +1,1664 @@ 
+/* Read and annotate call graph profile from the auto profile data file.
+   Copyright (C) 2014. Free Software Foundation, Inc.
+   Contributed by Dehao Chen (dehao@google.com)
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+#include <map>
+#include <vector>
+#include <set>
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tree.h"
+#include "tree-pass.h"
+#include "flags.h"
+#include "basic-block.h"
+#include "diagnostic-core.h"
+#include "gcov-io.h"
+#include "input.h"
+#include "profile.h"
+#include "langhooks.h"
+#include "opts.h"
+#include "tree-pass.h"
+#include "cfgloop.h"
+#include "tree-ssa-alias.h"
+#include "tree-cfg.h"
+#include "tree-cfgcleanup.h"
+#include "tree-ssa-operands.h"
+#include "tree-into-ssa.h"
+#include "internal-fn.h"
+#include "is-a.h"
+#include "gimple-expr.h"
+#include "gimple.h"
+#include "gimple-iterator.h"
+#include "gimple-ssa.h"
+#include "cgraph.h"
+#include "value-prof.h"
+#include "coverage.h"
+#include "params.h"
+#include "ipa-inline.h"
+#include "tree-inline.h"
+#include "auto-profile.h"
+
+/* The following routines implements AutoFDO optimization.
+
+   This optimization uses sampling profiles to annotate basic block counts
+   and uses heuristics to estimate branch probabilities.
+
+   There are three phases in AutoFDO:
+
+   Phase 1: Read profile from the profile data file.
+     The following info is read from the profile datafile:
+	* string_table: a map between function name and its index.
+	* autofdo_source_profile: a map from function_instance name to
+	  function_instance. This is represented as a forest of
+	  function_instances.
+	* WorkingSet: a histogram of how many instructions are covered for a
+	given percentage of total cycles.
+
+   Phase 2: Early inline + VPT.
+     Early inline uses autofdo_source_profile to find if a callsite is:
+	* inlined in the profiled binary.
+	* callee body is hot in the profiling run.
+     If both condition satisfies, early inline will inline the callsite
+     regardless of the code growth.
+     Phase 2 is an iterative process. During each iteration, we also check
+     if an indirect callsite is promoted and inlined in the profiling run.
+     If yes, vpt will happen to force promote it and in the next iteration,
+     einline will inline the promoted callsite in the next iteration.
+
+   Phase 3: Annotate control flow graph.
+     AutoFDO uses a separate pass to:
+	* Annotate basic block count
+	* Estimate branch probability
+
+   After the above 3 phases, all profile is readily annotated on the GCC IR.
+   AutoFDO tries to reuse all FDO infrastructure as much as possible to make
+   use of the profile. E.g. it uses existing mechanism to calculate the basic
+   block/edge frequency, as well as the cgraph node/edge count.
+*/
+
+#define DEFAULT_AUTO_PROFILE_FILE "fbdata.afdo"
+
+namespace autofdo {
+
+/* Represent a source location: (function_decl, lineno).  */
+typedef std::pair<tree, unsigned> decl_lineno;
+
+/* Represent an inline stack. vector[0] is the leaf node.  */
+typedef std::vector<decl_lineno> inline_stack;
+
+/* String array that stores function names.  */
+typedef std::vector<const char *> string_vector;
+
+/* Map from function name's index in string_table to target's
+   execution count.  */
+typedef std::map<unsigned, gcov_type> icall_target_map;
+
+/* Set of gimple stmts. Used to track if the stmt has already been promoted
+   to direct call.  */
+typedef std::set<gimple> stmt_set;
+
+/* Represent count info of an inline stack.  */
+struct count_info
+{
+  /* Sampled count of the inline stack.  */
+  gcov_type count;
+
+  /* Map from indirect call target to its sample count.  */
+  icall_target_map targets;
+
+  /* Whether this inline stack is already used in annotation. 
+
+     Each inline stack should only be used to annotate IR once.
+     This will be enforced when instruction-level discriminator
+     is supported.  */
+  bool annotated;
+};
+
+/* operator< for "const char *".  */
+struct string_compare
+{
+  bool operator() (const char *a, const char *b) const
+    { return strcmp (a, b) < 0; }
+};
+
+/* Store a string array, indexed by string position in the array.  */
+class string_table {
+public:
+  static string_table *create ();
+
+  /* For a given string, returns its index.  */
+  int get_index (const char *name) const;
+
+  /* For a given decl, returns the index of the decl name.  */
+  int get_index_by_decl (tree decl) const;
+
+  /* For a given index, returns the string.  */
+  const char *get_name (int index) const;
+
+private:
+  string_table () {}
+  bool read ();
+
+  typedef std::map<const char *, unsigned, string_compare> string_index_map;
+  string_vector vector_;
+  string_index_map map_;
+};
+
+/* Profile of a function instance:
+     1. total_count of the function.
+     2. head_count of the function (only valid when function is a top-level
+	function_instance, i.e. it is the original copy instead of the
+	inlined copy).
+     3. map from source location (decl_lineno) of the inlined callsite to
+	profile (count_info).
+     4. map from callsite to callee function_instance.  */
+class function_instance {
+public:
+  typedef std::vector<function_instance *> function_instance_stack;
+
+  /* Read the profile and return a function_instance with head count as
+     HEAD_COUNT. Recursively read callsites to create nested function_instances
+     too. STACK is used to track the recursive creation process.  */
+  static function_instance *read_function_instance (
+      function_instance_stack *stack, gcov_type head_count);
+
+  /* Recursively deallocate all callsites (nested function_instances).  */
+  ~function_instance ();
+
+  /* Accessors.  */
+  int name () const { return name_; }
+  gcov_type total_count () const { return total_count_; }
+  gcov_type head_count () const { return head_count_; }
+
+  /* Recursively traverse STACK starting from LEVEL to find the corresponding
+     function_instance.  */
+  function_instance *get_function_instance (const inline_stack &stack,
+					    unsigned level);
+
+  /* Store the profile info for LOC in INFO. Return TRUE if profile info
+     is found.  */
+  bool get_count_info (location_t loc, count_info *info) const;
+
+  /* Read the inlined indirect call target profile for STMT and store it in
+     MAP, return the total count for all inlined indirect calls.  */
+  gcov_type find_icall_target_map (gimple stmt, icall_target_map *map) const;
+
+  /* Sum of counts that is used during annotation.  */
+  gcov_type total_annotated_count () const;
+
+  /* Mark LOC as annotated.  */
+  void mark_annotated (location_t loc);
+
+private:
+  /* Callsite, represented as (decl_lineno, callee_function_name_index).  */
+  typedef std::pair<unsigned, unsigned> callsite;
+
+  /* Map from callsite to callee function_instance.  */
+  typedef std::map<callsite, function_instance *> callsite_map;
+ 
+  function_instance (unsigned name, gcov_type head_count)
+      : name_(name), total_count_(0), head_count_(head_count) {}
+
+  /* Traverse callsites of the current function_instance to find one at the
+     location of LINENO and callee name represented in DECL.  */
+  function_instance *get_function_instance_by_decl (
+      unsigned lineno, tree decl) const;
+
+  /* Map from source location (decl_lineno) to profile (count_info).  */
+  typedef std::map<unsigned, count_info> position_count_map;
+
+  /* function_instance name index in the string_table.  */
+  unsigned name_;
+
+  /* Total sample count.  */
+  gcov_type total_count_;
+
+  /* Entry BB's sample count.  */
+  gcov_type head_count_;
+
+  /* Map from callsite location to callee function_instance.  */
+  callsite_map callsites;
+
+  /* Map from source location to count_info.  */
+  position_count_map pos_counts;
+};
+
+/* Profile for all functions.  */
+class autofdo_source_profile {
+public:
+  static autofdo_source_profile *create ()
+    {
+      autofdo_source_profile *map = new autofdo_source_profile ();
+
+      if (map->read ())
+	return map;
+      delete map;
+      return NULL;
+    }
+
+  ~autofdo_source_profile ();
+
+  /* For a given DECL, returns the top-level function_instance.  */
+  function_instance *get_function_instance_by_decl (tree decl) const;
+
+  /* Find count_info for a given gimple STMT. If found, store the count_info
+     in INFO and return true; otherwise return false.  */
+  bool get_count_info (gimple stmt, count_info *info) const;
+
+  /* Find total count of the callee of EDGE.  */
+  gcov_type get_callsite_total_count (struct cgraph_edge *edge) const;
+
+  /* Update value profile INFO for STMT from the inlined indirect callsite.
+     Return true if INFO is updated.  */
+  bool update_inlined_ind_target (gimple stmt, count_info *info);
+
+  /* Mark LOC as annotated.  */
+  void mark_annotated (location_t loc);
+
+private:
+  /* Map from function_instance name index (in string_table) to
+     function_instance.  */
+  typedef std::map<unsigned, function_instance *>
+      name_function_instance_map;
+
+  autofdo_source_profile () {}
+
+  /* Read AutoFDO profile and returns TRUE on success.  */
+  bool read ();
+
+  /* Return the function_instance in the profile that correspond to the
+     inline STACK.  */
+  function_instance *get_function_instance_by_inline_stack (
+      const inline_stack &stack) const;
+
+  name_function_instance_map map_;
+};
+
+/* Store the strings read from the profile data file.  */
+static string_table *afdo_string_table;
+
+/* Store the AutoFDO source profile.  */
+static autofdo_source_profile *afdo_source_profile;
+
+/* gcov_ctr_summary structure to store the profile_info.  */
+static struct gcov_ctr_summary *afdo_profile_info;
+
+/* Helper functions.  */
+
+/* Return the original name of NAME: strip the suffix that starts
+   with '.'  */
+
+static const char *get_original_name (const char *name)
+{
+  char *ret = xstrdup (name);
+  char *find = strchr (ret, '.');
+  if (find != NULL)
+    *find = 0;
+  return ret;
+}
+
+/* Return the combined location, which is a 32bit integer in which
+   higher 16 bits stores the line offset of LOC to the start lineno
+   of DECL, The lower 16 bits stores the discrimnator.  */
+
+static unsigned
+get_combined_location (location_t loc, tree decl)
+{
+  /* TODO: allow more bits for line and less bits for discriminator.  */
+  return ((LOCATION_LINE (loc) - DECL_SOURCE_LINE (decl)) << 16);
+}
+
+/* Return the function decl of a given lexical BLOCK.  */
+
+static tree
+get_function_decl_from_block (tree block)
+{
+  tree decl;
+
+  if (LOCATION_LOCUS (BLOCK_SOURCE_LOCATION (block) == UNKNOWN_LOCATION))
+    return NULL_TREE;
+
+  for (decl = BLOCK_ABSTRACT_ORIGIN (block);
+       decl && (TREE_CODE (decl) == BLOCK);
+       decl = BLOCK_ABSTRACT_ORIGIN (decl))
+    if (TREE_CODE (decl) == FUNCTION_DECL)
+      break;
+  return decl;
+}
+
+/* Store inline stack for STMT in STACK.  */
+
+static void
+get_inline_stack (location_t locus, inline_stack *stack)
+{
+  if (LOCATION_LOCUS (locus) == UNKNOWN_LOCATION)
+    return;
+
+  tree block = LOCATION_BLOCK (locus);
+  if (block && TREE_CODE (block) == BLOCK)
+    {
+      int level = 0;
+      for (block = BLOCK_SUPERCONTEXT (block);
+	   block && (TREE_CODE (block) == BLOCK);
+	   block = BLOCK_SUPERCONTEXT (block))
+	{
+	  location_t tmp_locus = BLOCK_SOURCE_LOCATION (block);
+	  if (LOCATION_LOCUS (tmp_locus) == UNKNOWN_LOCATION)
+	    continue;
+
+	  tree decl = get_function_decl_from_block (block);
+	  stack->push_back (std::make_pair (
+	      decl, get_combined_location (locus, decl)));
+	  locus = tmp_locus;
+	  level++;
+	}
+    }
+  stack->push_back (std::make_pair (
+      current_function_decl,
+      get_combined_location (locus, current_function_decl)));
+}
+
+/* Return STMT's combined location, which is a 32bit integer in which
+   higher 16 bits stores the line offset of LOC to the start lineno
+   of DECL, The lower 16 bits stores the discrimnator.  */
+
+static unsigned
+get_relative_location_for_stmt (gimple stmt)
+{
+  location_t locus = gimple_location (stmt);
+  if (LOCATION_LOCUS (locus) == UNKNOWN_LOCATION)
+    return UNKNOWN_LOCATION;
+
+  for (tree block = gimple_block (stmt);
+       block && (TREE_CODE (block) == BLOCK);
+       block = BLOCK_SUPERCONTEXT (block))
+    if (LOCATION_LOCUS (BLOCK_SOURCE_LOCATION (block)) != UNKNOWN_LOCATION)
+      return get_combined_location (
+	  locus, get_function_decl_from_block (block));
+  return get_combined_location (locus, current_function_decl);
+}
+
+/* Return true if BB contains indirect call.  */
+
+static bool
+has_indirect_call (basic_block bb)
+{
+  gimple_stmt_iterator gsi;
+
+  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+    {
+      gimple stmt = gsi_stmt (gsi);
+      if (gimple_code (stmt) == GIMPLE_CALL
+	  && !gimple_call_internal_p (stmt)
+	  && (gimple_call_fn (stmt) == NULL
+	      || TREE_CODE (gimple_call_fn (stmt)) != FUNCTION_DECL))
+	return true;
+    }
+  return false;
+}
+
+/* Member functions for string_table.  */
+
+string_table *
+string_table::create ()
+{
+  string_table *map = new string_table();
+  if (map->read ())
+    return map;
+  delete map;
+  return NULL;
+}
+
+/* Return the index of a given function NAME.  */
+
+int
+string_table::get_index (const char *name) const
+{
+  if (name == NULL)
+    return -1;
+  string_index_map::const_iterator iter = map_.find (name);
+  if (iter == map_.end())
+    return -1;
+  else
+    return iter->second;
+}
+
+/* Return the index of a given function DECL.  */
+
+int
+string_table::get_index_by_decl (tree decl) const
+{
+  const char *name = get_original_name (
+      IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
+  int ret = get_index (name);
+  if (ret != -1)
+    return ret;
+  ret = get_index (lang_hooks.dwarf_name (decl, 0));
+  if (ret != -1)
+    return ret;
+  if (DECL_ABSTRACT_ORIGIN (decl))
+    return get_index_by_decl (DECL_ABSTRACT_ORIGIN (decl));
+  else
+    return -1;
+}
+
+/* Return the function name of a given INDEX.  */
+
+const char *
+string_table::get_name (int index) const
+{
+  gcc_assert (index > 0 && index < (int) vector_.size());
+  return vector_[index];
+}
+
+/* Read the string table. Return TRUE if reading is successful.  */
+
+bool
+string_table::read ()
+{
+  if (gcov_read_unsigned () != GCOV_TAG_AFDO_FILE_NAMES)
+    return false;
+  /* Skip the length of the section.  */
+  gcov_read_unsigned ();
+  /* Read in the file name table.  */
+  unsigned string_num = gcov_read_unsigned ();
+  for (unsigned i = 0; i < string_num; i++)
+    {
+      vector_.push_back (get_original_name (gcov_read_string ()));
+      map_[vector_.back()] = i;
+    }
+  return true;
+}
+
+
+/* Member functions for function_instance.  */
+
+function_instance::~function_instance ()
+{
+  for (callsite_map::iterator iter = callsites.begin();
+       iter != callsites.end(); ++iter)
+    delete iter->second;
+}
+
+/* Traverse callsites of the current function_instance to find one at the
+   location of LINENO and callee name represented in DECL.  */
+
+function_instance *
+function_instance::get_function_instance_by_decl (
+    unsigned lineno, tree decl) const
+{
+  int func_name_idx = afdo_string_table->get_index_by_decl (decl);
+  if (func_name_idx != -1)
+    {
+      callsite_map::const_iterator ret = callsites.find (
+	  std::make_pair (lineno, func_name_idx));
+      if (ret != callsites.end ())
+	return ret->second;
+    }
+  func_name_idx = afdo_string_table->get_index (
+      lang_hooks.dwarf_name (decl, 0));
+  if (func_name_idx != -1)
+    {
+      callsite_map::const_iterator ret = callsites.find (
+	  std::make_pair (lineno, func_name_idx));
+      if (ret != callsites.end ())
+	return ret->second;
+    }
+  if (DECL_ABSTRACT_ORIGIN (decl))
+    return get_function_instance_by_decl (lineno, DECL_ABSTRACT_ORIGIN (decl));
+  else
+    return NULL;
+}
+
+/* Recursively traverse STACK starting from LEVEL to find the corresponding
+   function_instance.  */
+
+function_instance *
+function_instance::get_function_instance (
+    const inline_stack &stack, unsigned level)
+{
+  if (level == 0)
+    return this;
+  function_instance *s =
+      get_function_instance_by_decl (stack[level].second, stack[level - 1].first);
+  if (s)
+    return s->get_function_instance (stack, level - 1);
+  else
+    return NULL;
+}
+
+/* Store the profile info for LOC in INFO. Return TRUE if profile info
+   is found.  */
+
+bool
+function_instance::get_count_info (location_t loc, count_info *info) const
+{
+  position_count_map::const_iterator iter = pos_counts.find (loc);
+  if (iter == pos_counts.end ())
+    return false;
+  *info = iter->second;
+  return true;
+}
+
+/* Mark LOC as annotated.  */
+
+void
+function_instance::mark_annotated (location_t loc)
+{
+  position_count_map::iterator iter = pos_counts.find (loc);
+  if (iter == pos_counts.end ())
+    return;
+  iter->second.annotated = true;
+}
+
+/* Read the inlinied indirect call target profile for STMT and store it in
+   MAP, return the total count for all inlined indirect calls.  */
+
+gcov_type
+function_instance::find_icall_target_map (
+    gimple stmt, icall_target_map *map) const
+{
+  gcov_type ret = 0;
+  unsigned stmt_offset = get_relative_location_for_stmt (stmt);
+
+  for (callsite_map::const_iterator iter = callsites.begin();
+       iter != callsites.end(); ++iter)
+    {
+      unsigned callee = iter->second->name();
+      /* Check if callsite location match the stmt.  */
+      if (iter->first.first != stmt_offset)
+	continue;
+      struct cgraph_node *node = find_func_by_profile_id (
+	  (unsigned long long) afdo_string_table->get_name (callee));
+      if (node == NULL)
+	continue;
+      if (!check_ic_target (stmt, node))
+	continue;
+      (*map)[callee] = iter->second->total_count ();
+      ret += iter->second->total_count ();
+    }
+  return ret;
+}
+
+/* Read the profile and create a function_instance with head count as
+   HEAD_COUNT. Recursively read callsites to create nested function_instances
+   too. STACK is used to track the recursive creation process.  */
+
+/* function instance profile format:
+
+   ENTRY_COUNT: 8 bytes
+   NAME_INDEX: 4 bytes
+   NUM_POS_COUNTS: 4 bytes
+   NUM_CALLSITES: 4 byte
+   POS_COUNT_1:
+     POS_1_OFFSET: 4 bytes
+     NUM_TARGETS: 4 bytes
+     COUNT: 8 bytes
+     TARGET_1:
+       VALUE_PROFILE_TYPE: 4 bytes
+       TARGET_IDX: 8 bytes
+       COUNT: 8 bytes
+     TARGET_2
+     ...
+     TARGET_n
+   POS_COUNT_2
+   ...
+   POS_COUNT_N
+   CALLSITE_1:
+     CALLSITE_1_OFFSET: 4 bytes
+     FUNCTION_INSTANCE_PROFILE (nested)
+   CALLSITE_2
+   ...
+   CALLSITE_n.  */
+
+function_instance *
+function_instance::read_function_instance (
+    function_instance_stack *stack, gcov_type head_count)
+{
+  unsigned name = gcov_read_unsigned ();
+  unsigned num_pos_counts = gcov_read_unsigned ();
+  unsigned num_callsites = gcov_read_unsigned ();
+  function_instance *s = new function_instance (name, head_count);
+  stack->push_back(s);
+
+  for (unsigned i = 0; i < num_pos_counts; i++)
+    {
+      unsigned offset = gcov_read_unsigned () & 0xffff0000;
+      unsigned num_targets = gcov_read_unsigned ();
+      gcov_type count = gcov_read_counter ();
+      s->pos_counts[offset].count = count;
+      for (unsigned j = 0; j < stack->size(); j++)
+	(*stack)[j]->total_count_ += count;
+      for (unsigned j = 0; j < num_targets; j++)
+	{
+	  /* Only indirect call target histogram is supported now.  */
+	  gcov_read_unsigned ();
+	  gcov_type target_idx = gcov_read_counter ();
+	  s->pos_counts[offset].targets[target_idx] =
+	      gcov_read_counter ();
+	}
+    }
+  for (unsigned i = 0; i < num_callsites; i++) {
+    unsigned offset = gcov_read_unsigned ();
+    function_instance *callee_function_instance =
+	read_function_instance (stack, 0);
+    s->callsites[std::make_pair (offset, callee_function_instance->name ())] =
+	callee_function_instance;
+  }
+  stack->pop_back();
+  return s;
+}
+
+/* Sum of counts that is used during annotation.  */
+
+gcov_type
+function_instance::total_annotated_count () const
+{
+  gcov_type ret = 0;
+  for (callsite_map::const_iterator iter = callsites.begin();
+       iter != callsites.end(); ++iter)
+    ret += iter->second->total_annotated_count ();
+  for (position_count_map::const_iterator iter = pos_counts.begin();
+       iter != pos_counts.end(); ++iter)
+    if (iter->second.annotated)
+      ret += iter->second.count;
+  return ret;
+}
+
+
+/* Member functions for autofdo_source_profile.  */
+
+autofdo_source_profile::~autofdo_source_profile ()
+{
+  for (name_function_instance_map::const_iterator iter = map_.begin ();
+       iter != map_.end (); ++iter)
+    delete iter->second;
+}
+
+/* For a given DECL, returns the top-level function_instance.  */
+
+function_instance *
+autofdo_source_profile::get_function_instance_by_decl (tree decl) const
+{
+  int index = afdo_string_table->get_index_by_decl (decl);
+  if (index == -1)
+    return NULL;
+  name_function_instance_map::const_iterator ret = map_.find (index);
+  return ret == map_.end() ? NULL : ret->second;
+}
+
+/* Find count_info for a given gimple STMT. If found, store the count_info
+   in INFO and return true; otherwise return false.  */
+
+bool
+autofdo_source_profile::get_count_info (gimple stmt, count_info *info) const
+{
+  if (LOCATION_LOCUS (gimple_location (stmt)) == cfun->function_end_locus)
+    return false;
+
+  inline_stack stack;
+  get_inline_stack (gimple_location (stmt), &stack);
+  if (stack.size () == 0)
+    return false;
+  function_instance *s = get_function_instance_by_inline_stack (stack);
+  if (s == NULL)
+    return false;
+  return s->get_count_info (stack[0].second, info);
+}
+
+/* Mark LOC as annotated.  */
+
+void
+autofdo_source_profile::mark_annotated (location_t loc) {
+  inline_stack stack;
+  get_inline_stack (loc, &stack);
+  if (stack.size () == 0)
+    return;
+  function_instance *s = get_function_instance_by_inline_stack (stack);
+  if (s == NULL)
+    return;
+  s->mark_annotated (stack[0].second);
+}
+
+/* Update value profile INFO for STMT from the inlined indirect callsite.
+   Return true if INFO is updated.  */
+
+bool
+autofdo_source_profile::update_inlined_ind_target (
+    gimple stmt, count_info *info)
+{
+  if (LOCATION_LOCUS (gimple_location (stmt)) == cfun->function_end_locus)
+    return false;
+
+  count_info old_info;
+  get_count_info (stmt, &old_info);
+  gcov_type total = 0;
+  for (icall_target_map::const_iterator iter = old_info.targets.begin();
+       iter != old_info.targets.end(); ++iter)
+    total += iter->second;
+
+  /* Program behavior changed, original promoted (and inlined) target is not
+     hot any more. Will avoid promote the original target.
+
+     To check if original promoted target is still hot, we check the total
+     count of the unpromoted targets (stored in old_info). If it is no less
+     than half of the callsite count (stored in INFO), the original promoted
+     target is considered not hot any more.  */
+  if (total >= info->count / 2)
+    return false;
+
+  inline_stack stack;
+  get_inline_stack (gimple_location (stmt), &stack);
+  if (stack.size () == 0)
+    return false;
+  function_instance *s = get_function_instance_by_inline_stack (stack);
+  if (s == NULL)
+    return false;
+  icall_target_map map;
+  if (s->find_icall_target_map (stmt, &map) == 0)
+    return false;
+  for (icall_target_map::const_iterator iter = map.begin();
+       iter != map.end(); ++iter)
+    info->targets[iter->first] = iter->second;
+  return true;
+}
+
+/* Find total count of the callee of EDGE.  */
+
+gcov_type
+autofdo_source_profile::get_callsite_total_count (
+    struct cgraph_edge *edge) const
+{
+  inline_stack stack;
+  stack.push_back (std::make_pair(edge->callee->decl, 0));
+  get_inline_stack (gimple_location (edge->call_stmt), &stack);
+
+  function_instance *s = get_function_instance_by_inline_stack (stack);
+  if (s == NULL ||
+      afdo_string_table->get_index (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (edge->callee->decl))) != s->name ())
+    return 0;
+  else
+    return s->total_count ();
+}
+
+/* Read AutoFDO profile and returns TRUE on success.  */
+
+/* source profile format:
+
+   GCOV_TAG_AFDO_FUNCTION: 4 bytes
+   LENGTH: 4 bytes
+   NUM_FUNCTIONS: 4 bytes
+   FUNCTION_INSTANCE_1
+   FUNCTION_INSTANCE_2
+   ...
+   FUNCTION_INSTANCE_N.  */
+
+bool
+autofdo_source_profile::read ()
+{
+  if (gcov_read_unsigned () != GCOV_TAG_AFDO_FUNCTION)
+    {
+      inform (0, "Not expected TAG.");
+      return false;
+    }
+
+  /* Skip the length of the section.  */
+  gcov_read_unsigned ();
+
+  /* Read in the function/callsite profile, and store it in local
+     data structure.  */
+  unsigned function_num = gcov_read_unsigned ();
+  for (unsigned i = 0; i < function_num; i++)
+    {
+      function_instance::function_instance_stack stack;
+      function_instance *s = function_instance::read_function_instance (
+	  &stack, gcov_read_counter ());
+      afdo_profile_info->sum_all += s->total_count ();
+      map_[s->name ()] = s;
+    }
+  return true;
+}
+
+/* Return the function_instance in the profile that correspond to the
+   inline STACK.  */
+
+function_instance *
+autofdo_source_profile::get_function_instance_by_inline_stack (
+    const inline_stack &stack) const
+{
+  name_function_instance_map::const_iterator iter = map_.find (
+      afdo_string_table->get_index_by_decl (
+	  stack[stack.size() - 1].first));
+  return iter == map_.end()
+      ? NULL
+      : iter->second->get_function_instance (stack, stack.size() - 1);
+}
+
+/* Module profile is only used by LIPO. Here we simply ignore it.  */
+
+static void
+fake_read_autofdo_module_profile ()
+{
+  /* Read in the module info.  */
+  gcov_read_unsigned ();
+
+  /* Skip the length of the section.  */
+  gcov_read_unsigned ();
+
+  /* Read in the file name table.  */
+  unsigned total_module_num = gcov_read_unsigned ();
+  gcc_assert (total_module_num == 0);
+}
+
+static void
+read_profile (void)
+{
+  if (gcov_open (auto_profile_file, 1) == 0)
+    error ("Cannot open profile file %s.", auto_profile_file);
+
+  if (gcov_read_unsigned () != GCOV_DATA_MAGIC)
+    error ("AutoFDO profile magic number does not mathch.");
+
+  /* Skip the version number.  */
+  gcov_read_unsigned ();
+
+  /* Skip the empty integer.  */
+  gcov_read_unsigned ();
+
+  /* string_table.  */
+  afdo_string_table = string_table::create ();
+  if (afdo_string_table == NULL)
+    error ("Cannot read string table from %s.", auto_profile_file);
+
+  /* autofdo_source_profile.  */
+  afdo_source_profile = autofdo_source_profile::create ();
+  if (afdo_source_profile == NULL)
+    error ("Cannot read function profile from %s.", auto_profile_file);
+
+  /* autofdo_module_profile.  */
+  fake_read_autofdo_module_profile ();
+
+  /* Read in the working set.  */
+  if (gcov_read_unsigned () != GCOV_TAG_AFDO_WORKING_SET)
+    error ("Cannot read working set from %s.", auto_profile_file);
+
+  /* Skip the length of the section.  */
+  gcov_read_unsigned ();
+  gcov_working_set_t set[128];
+  for (unsigned i = 0; i < 128; i++)
+    {
+      set[i].num_counters = gcov_read_unsigned ();
+      set[i].min_counter = gcov_read_counter ();
+    }
+  add_working_set (set);
+}
+
+/* From AutoFDO profiles, find values inside STMT for that we want to measure
+   histograms for indirect-call optimization.  */
+
+static void
+afdo_indirect_call (gimple_stmt_iterator *gsi, const icall_target_map &map,
+		    bool transform)
+{
+  gimple stmt = gsi_stmt (*gsi);
+  tree callee;
+
+  if (map.size() == 0 || gimple_code (stmt) != GIMPLE_CALL
+      || gimple_call_fndecl (stmt) != NULL_TREE)
+    return;
+
+  callee = gimple_call_fn (stmt);
+
+  histogram_value hist = gimple_alloc_histogram_value (
+      cfun, HIST_TYPE_INDIR_CALL, stmt, callee);
+  hist->n_counters = 3;
+  hist->hvalue.counters =  XNEWVEC (gcov_type, hist->n_counters);
+  gimple_add_histogram_value (cfun, stmt, hist);
+
+  gcov_type total = 0;
+  icall_target_map::const_iterator max_iter = map.end();
+
+  for (icall_target_map::const_iterator iter = map.begin();
+       iter != map.end(); ++iter)
+    {
+      total += iter->second;
+      if (max_iter == map.end() || max_iter->second < iter->second)
+	max_iter = iter;
+    }
+
+  hist->hvalue.counters[0] = (unsigned long long)
+      afdo_string_table->get_name (max_iter->first);
+  hist->hvalue.counters[1] = max_iter->second;
+  hist->hvalue.counters[2] = total;
+
+  if (!transform)
+    return;
+
+  if (gimple_ic_transform (gsi))
+    {
+      struct cgraph_edge *indirect_edge =
+	  cgraph_node::get (current_function_decl)->get_edge (stmt);
+      struct cgraph_node *direct_call =
+	  find_func_by_profile_id ((int)hist->hvalue.counters[0]);
+      if (DECL_STRUCT_FUNCTION (direct_call->decl) == NULL)
+	return;
+      struct cgraph_edge *new_edge =
+	  indirect_edge->make_speculative (direct_call, 0, 0);
+      new_edge->redirect_call_stmt_to_callee ();
+      gimple_remove_histogram_value (cfun, stmt, hist);
+      inline_call (new_edge, true, NULL, NULL, false);
+      return;
+    }
+  return;
+}
+
+/* From AutoFDO profiles, find values inside STMT for that we want to measure
+   histograms and adds them to list VALUES.  */
+
+static void
+afdo_vpt (gimple_stmt_iterator *gsi, const icall_target_map &map,
+	  bool transform)
+{
+  afdo_indirect_call (gsi, map, transform);
+}
+
+typedef std::set<basic_block> bb_set;
+typedef std::set<edge> edge_set;
+
+static bool
+is_bb_annotated (const basic_block bb, const bb_set &annotated)
+{
+  return annotated.find(bb) != annotated.end();
+}
+
+static void
+set_bb_annotated (basic_block bb, bb_set *annotated)
+{
+  annotated->insert(bb);
+}
+
+static bool
+is_edge_annotated (const edge e, const edge_set &annotated)
+{
+  return annotated.find(e) != annotated.end();
+}
+
+static void
+set_edge_annotated (edge e, edge_set *annotated)
+{
+  annotated->insert(e);
+}
+
+/* For a given BB, set its execution count. Attach value profile if a stmt
+   is not in PROMOTED, because we only want to promot an indirect call once.
+   Return TRUE if BB is annotated.  */
+
+static bool
+afdo_set_bb_count (basic_block bb, const stmt_set &promoted)
+{
+  gimple_stmt_iterator gsi;
+  edge e;
+  edge_iterator ei;
+  gcov_type max_count = 0;
+  bool has_annotated = false;
+
+  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+    {
+      count_info info;
+      gimple stmt = gsi_stmt (gsi);
+      if (gimple_clobber_p (stmt) || is_gimple_debug (stmt))
+	continue;
+      if (afdo_source_profile->get_count_info (stmt, &info))
+	{
+	  if (info.count > max_count)
+	    max_count = info.count;
+	  has_annotated = true;
+	  if (info.targets.size() > 0 && promoted.find (stmt) == promoted.end ())
+	    afdo_vpt (&gsi, info.targets, false);
+	}
+    }
+
+  if (!has_annotated)
+    return false;
+
+  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+    afdo_source_profile->mark_annotated (gimple_location (gsi_stmt (gsi)));
+  for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+    {
+      gimple phi = gsi_stmt (gsi);
+      size_t i;
+      for (i = 0; i < gimple_phi_num_args (phi); i++)
+	afdo_source_profile->mark_annotated (gimple_phi_arg_location (phi, i));
+    }
+  FOR_EACH_EDGE (e, ei, bb->succs)
+    afdo_source_profile->mark_annotated (e->goto_locus);
+
+  bb->count = max_count;
+  return true;
+}
+
+/* BB1 and BB2 are in an equivalent class iff:
+   1. BB1 dominates BB2.
+   2. BB2 post-dominates BB1.
+   3. BB1 and BB2 are in the same loop nest.
+   This function finds the equivalent class for each basic block, and
+   stores a pointer to the first BB in its equivalent class. Meanwhile,
+   set bb counts for the same equivalent class to be idenical. Update
+   ANNOTATED_BB for the first BB in its equivalent class.  */
+
+static void
+afdo_find_equiv_class (bb_set *annotated_bb)
+{
+  basic_block bb;
+
+  FOR_ALL_BB_FN (bb, cfun)
+    bb->aux = NULL;
+
+  FOR_ALL_BB_FN (bb, cfun)
+    {
+      vec<basic_block> dom_bbs;
+      basic_block bb1;
+      int i;
+
+      if (bb->aux != NULL)
+	continue;
+      bb->aux = bb;
+      dom_bbs = get_dominated_by (CDI_DOMINATORS, bb);
+      FOR_EACH_VEC_ELT (dom_bbs, i, bb1)
+	if (bb1->aux == NULL
+	    && dominated_by_p (CDI_POST_DOMINATORS, bb, bb1)
+	    && bb1->loop_father == bb->loop_father)
+	  {
+	    bb1->aux = bb;
+	    if (bb1->count > bb->count && is_bb_annotated (bb1, *annotated_bb))
+	      {
+		bb->count = MAX (bb->count, bb1->count);
+		set_bb_annotated (bb, annotated_bb);
+	      }
+	  }
+      dom_bbs = get_dominated_by (CDI_POST_DOMINATORS, bb);
+      FOR_EACH_VEC_ELT (dom_bbs, i, bb1)
+	if (bb1->aux == NULL
+	    && dominated_by_p (CDI_DOMINATORS, bb, bb1)
+	    && bb1->loop_father == bb->loop_father)
+	  {
+	    bb1->aux = bb;
+	    if (bb1->count > bb->count && is_bb_annotated (bb1, *annotated_bb))
+	      {
+		bb->count = MAX (bb->count, bb1->count);
+		set_bb_annotated (bb, annotated_bb);
+	      }
+	  }
+    }
+}
+
+/* If a basic block's count is known, and only one of its in/out edges' count
+   is unknown, its count can be calculated. Meanwhile, if all of the in/out
+   edges' counts are known, then the basic block's unknown count can also be
+   calculated.
+   IS_SUCC is true if out edges of a basic blocks are examined.
+   Update ANNOTATED_BB and ANNOTATED_EDGE accordingly.
+   Return TRUE if any basic block/edge count is changed.  */
+
+static bool
+afdo_propagate_edge (bool is_succ,
+		     bb_set *annotated_bb, edge_set *annotated_edge)
+{
+  basic_block bb;
+  bool changed = false;
+
+  FOR_EACH_BB_FN (bb, cfun)
+    {
+      edge e, unknown_edge = NULL;
+      edge_iterator ei;
+      int num_unknown_edge = 0;
+      gcov_type total_known_count = 0;
+
+      FOR_EACH_EDGE (e, ei, is_succ ? bb->succs : bb->preds)
+	if (!is_edge_annotated (e, *annotated_edge))
+	  num_unknown_edge ++, unknown_edge = e;
+	else
+	  total_known_count += e->count;
+
+      if (num_unknown_edge == 0)
+	{
+	  if (total_known_count > bb->count)
+	    {
+	      bb->count = total_known_count;
+	      changed = true;
+	    }
+	  if (!is_bb_annotated (bb, *annotated_bb))
+	    {
+	      set_bb_annotated (bb, annotated_bb);
+	      changed = true;
+	    }
+	}
+      else if (num_unknown_edge == 1
+	       && is_bb_annotated (bb, *annotated_bb))
+	{
+	  if (bb->count >= total_known_count)
+	    unknown_edge->count = bb->count - total_known_count;
+	  else
+	    unknown_edge->count = 0;
+	  set_edge_annotated (unknown_edge, annotated_edge);
+	  changed = true;
+	}
+    }
+  return changed;
+}
+
+/* Special propagation for circuit expressions. Because GCC translates
+   control flow into data flow for circuit expressions. E.g.
+   BB1:
+   if (a && b)
+     BB2
+   else
+     BB3
+
+   will be translated into:
+
+   BB1:
+     if (a)
+       goto BB.t1
+     else
+       goto BB.t3
+   BB.t1:
+     if (b)
+       goto BB.t2
+     else
+       goto BB.t3
+   BB.t2:
+     goto BB.t3
+   BB.t3:
+     tmp = PHI (0 (BB1), 0 (BB.t1), 1 (BB.t2)
+     if (tmp)
+       goto BB2
+     else
+       goto BB3
+
+   In this case, we need to propagate through PHI to determine the edge
+   count of BB1->BB.t1, BB.t1->BB.t2.
+   Update ANNOTATED_EDGE accordingly.  */
+
+static void
+afdo_propagate_circuit (const bb_set &annotated_bb, edge_set *annotated_edge)
+{
+  basic_block bb;
+  FOR_ALL_BB_FN (bb, cfun)
+    {
+      gimple phi_stmt;
+      tree cmp_rhs, cmp_lhs;
+      gimple cmp_stmt = last_stmt (bb);
+      edge e;
+      edge_iterator ei;
+
+      if (!cmp_stmt || gimple_code (cmp_stmt) != GIMPLE_COND)
+	continue;
+      cmp_rhs = gimple_cond_rhs (cmp_stmt);
+      cmp_lhs = gimple_cond_lhs (cmp_stmt);
+      if (!TREE_CONSTANT (cmp_rhs)
+	  || !(integer_zerop (cmp_rhs) || integer_onep (cmp_rhs)))
+	continue;
+      if (TREE_CODE (cmp_lhs) != SSA_NAME)
+	continue;
+      if (!is_bb_annotated (bb, annotated_bb))
+	continue;
+      phi_stmt = SSA_NAME_DEF_STMT (cmp_lhs);
+      while (phi_stmt && gimple_code (phi_stmt) == GIMPLE_ASSIGN
+	     && gimple_assign_single_p (phi_stmt)
+	     && TREE_CODE (gimple_assign_rhs1 (phi_stmt)) == SSA_NAME)
+	phi_stmt = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (phi_stmt));
+      if (!phi_stmt || gimple_code (phi_stmt) != GIMPLE_PHI)
+	continue;
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	{
+	  unsigned i, total = 0;
+	  edge only_one;
+	  bool check_value_one = (((integer_onep (cmp_rhs))
+		    ^ (gimple_cond_code (cmp_stmt) == EQ_EXPR))
+		    ^ ((e->flags & EDGE_TRUE_VALUE) != 0));
+	  if (!is_edge_annotated (e, *annotated_edge))
+	    continue;
+	  for (i = 0; i < gimple_phi_num_args (phi_stmt); i++)
+	    {
+	      tree val = gimple_phi_arg_def (phi_stmt, i);
+	      edge ep = gimple_phi_arg_edge (phi_stmt, i);
+
+	      if (!TREE_CONSTANT (val) || !(integer_zerop (val)
+		  || integer_onep (val)))
+		continue;
+	      if (check_value_one ^ integer_onep (val))
+		continue;
+	      total++;
+	      only_one = ep;
+	      if (e->probability == 0
+		  && !is_edge_annotated (ep, *annotated_edge))
+		{
+		  ep->probability = 0;
+		  ep->count = 0;
+		  set_edge_annotated (ep, annotated_edge);
+		}
+	    }
+	  if (total == 1 && !is_edge_annotated (only_one, *annotated_edge))
+	    {
+	      only_one->probability = e->probability;
+	      only_one->count = e->count;
+	      set_edge_annotated (only_one, annotated_edge);
+	    }
+	}
+    }
+}
+
+/* Propagate the basic block count and edge count on the control flow
+   graph. We do the propagation iteratively until stablize.  */
+
+static void
+afdo_propagate (bb_set *annotated_bb, edge_set *annotated_edge)
+{
+  basic_block bb;
+  bool changed = true;
+  int i = 0;
+
+  FOR_ALL_BB_FN (bb, cfun)
+    {
+      bb->count = ((basic_block) bb->aux)->count;
+      if (is_bb_annotated ((const basic_block) bb->aux, *annotated_bb))
+	set_bb_annotated (bb, annotated_bb);
+    }
+
+  while (changed && i++ < 10)
+    {
+      changed = false;
+
+      if (afdo_propagate_edge (true, annotated_bb, annotated_edge))
+	changed = true;
+      if (afdo_propagate_edge (false, annotated_bb, annotated_edge))
+	changed = true;
+      afdo_propagate_circuit (*annotated_bb, annotated_edge);
+    }
+}
+
+/* Propagate counts on control flow graph and calculate branch
+   probabilities.  */
+
+static void
+afdo_calculate_branch_prob (bb_set *annotated_bb, edge_set *annotated_edge)
+{
+  basic_block bb;
+  bool has_sample = false;
+
+  FOR_EACH_BB_FN (bb, cfun)
+    if (bb->count > 0)
+      has_sample = true;
+
+  if (!has_sample)
+    return;
+
+  calculate_dominance_info (CDI_POST_DOMINATORS);
+  calculate_dominance_info (CDI_DOMINATORS);
+  loop_optimizer_init (0);
+
+  afdo_find_equiv_class (annotated_bb);
+  afdo_propagate (annotated_bb, annotated_edge);
+
+  FOR_EACH_BB_FN (bb, cfun)
+    {
+      edge e;
+      edge_iterator ei;
+      int num_unknown_succ = 0;
+      gcov_type total_count = 0;
+
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	{
+	  if (!is_edge_annotated (e, *annotated_edge))
+	    num_unknown_succ ++;
+	  else
+	    total_count += e->count;
+	}
+      if (num_unknown_succ == 0 && total_count > 0)
+	{
+	  FOR_EACH_EDGE (e, ei, bb->succs)
+	    e->probability =
+		(double) e->count * REG_BR_PROB_BASE / total_count;
+	}
+    }
+  FOR_ALL_BB_FN (bb, cfun)
+    {
+      edge e;
+      edge_iterator ei;
+
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	e->count =
+		(double) bb->count * e->probability / REG_BR_PROB_BASE;
+      bb->aux = NULL;
+    }
+
+  loop_optimizer_finalize ();
+  free_dominance_info (CDI_DOMINATORS);
+  free_dominance_info (CDI_POST_DOMINATORS);
+}
+
+/* Perform value profile transformation using AutoFDO profile. Add the
+   promoted stmts to PROMOTED_STMTS. Return TRUE if there is any
+   indirect call promoted.  */
+
+static bool
+afdo_vpt_for_early_inline (stmt_set *promoted_stmts)
+{
+  basic_block bb;
+  if (afdo_source_profile->get_function_instance_by_decl (
+      current_function_decl) == NULL)
+    return false;
+
+  compute_inline_parameters (cgraph_node::get (current_function_decl), true);
+
+  bool has_vpt = false;
+  FOR_EACH_BB_FN (bb, cfun)
+    {
+      if (!has_indirect_call (bb))
+	continue;
+      gimple_stmt_iterator gsi;
+
+      gcov_type bb_count = 0;
+      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	{
+	  count_info info;
+	  gimple stmt = gsi_stmt (gsi);
+	  if (afdo_source_profile->get_count_info (stmt, &info))
+	    bb_count = MAX (bb_count, info.count);
+	}
+
+      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	{
+	  gimple stmt = gsi_stmt (gsi);
+	  /* IC_promotion and early_inline_2 is done in multiple iterations.
+	     No need to promoted the stmt if its in promoted_stmts (means
+	     it is already been promoted in the previous iterations).  */
+	  if (gimple_code (stmt) != GIMPLE_CALL
+	      || gimple_call_fn (stmt) == NULL
+	      || TREE_CODE (gimple_call_fn (stmt)) == FUNCTION_DECL
+	      || promoted_stmts->find (stmt) != promoted_stmts->end ())
+	    continue;
+
+	  count_info info;
+	  afdo_source_profile->get_count_info (stmt, &info);
+	  info.count = bb_count;
+	  if (afdo_source_profile->update_inlined_ind_target (stmt, &info))
+	    {
+	      /* Promote the indirect call and update the promoted_stmts.  */
+	      promoted_stmts->insert (stmt);
+	      afdo_vpt (&gsi, info.targets, true);
+	      has_vpt = true;
+	    }
+	}
+    }
+  if (has_vpt)
+    {
+      optimize_inline_calls (current_function_decl);
+      return true;
+    }
+  else
+    return false;
+}
+
+/* Annotate auto profile to the control flow graph. Do not annotate value
+   profile for stmts in PROMOTED_STMTS.  */
+
+static void
+afdo_annotate_cfg (const stmt_set &promoted_stmts)
+{
+  basic_block bb;
+  bb_set annotated_bb;
+  edge_set annotated_edge;
+  const function_instance *s =
+      afdo_source_profile->get_function_instance_by_decl (
+      current_function_decl);
+
+  if (s == NULL)
+    return;
+  cgraph_node::get (current_function_decl)->count = s->head_count ();
+  ENTRY_BLOCK_PTR_FOR_FN (cfun)->count = s->head_count ();
+  gcov_type max_count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
+
+  FOR_EACH_BB_FN (bb, cfun)
+    {
+      edge e;
+      edge_iterator ei;
+
+      bb->count = 0;
+      FOR_EACH_EDGE (e, ei, bb->succs)
+	e->count = 0;
+
+      if (afdo_set_bb_count (bb, promoted_stmts))
+	set_bb_annotated (bb, &annotated_bb);
+      if (bb->count > max_count)
+	max_count = bb->count;
+    }
+  if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count >
+      ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb->count)
+    {
+      ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb->count =
+	  ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
+      set_bb_annotated (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, &annotated_bb);
+    }
+  if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count >
+      EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->count)
+    {
+      EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->count =
+	  ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
+      set_bb_annotated (EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb, &annotated_bb);
+    }
+  afdo_source_profile->mark_annotated (
+      DECL_SOURCE_LOCATION (current_function_decl));
+  afdo_source_profile->mark_annotated (cfun->function_start_locus);
+  afdo_source_profile->mark_annotated (cfun->function_end_locus);
+  if (max_count > 0)
+    {
+      afdo_calculate_branch_prob (&annotated_bb, &annotated_edge);
+      counts_to_freqs ();
+      profile_status_for_fn (cfun) = PROFILE_READ;
+    }
+  if (flag_value_profile_transformations)
+    gimple_value_profile_transformations ();
+}
+
+/* Wrapper function to invoke early inliner.  */
+
+static void early_inline ()
+{
+  compute_inline_parameters (cgraph_node::get (current_function_decl), true);
+  unsigned todo = early_inliner (cfun);
+  if (todo & TODO_update_ssa_any)
+    update_ssa (TODO_update_ssa);
+}
+
+/* Use AutoFDO profile to annoate the control flow graph.
+   Return the todo flag.  */
+
+static unsigned int
+auto_profile (void)
+{
+  struct cgraph_node *node;
+
+  if (symtab->state == FINISHED)
+    return 0;
+
+  init_node_map (true);
+  profile_info = autofdo::afdo_profile_info;
+
+  FOR_EACH_FUNCTION (node)
+    {
+      if (!gimple_has_body_p (node->decl))
+	continue;
+
+      /* Don't profile functions produced for builtin stuff.  */
+      if (DECL_SOURCE_LOCATION (node->decl) == BUILTINS_LOCATION)
+	continue;
+
+      push_cfun (DECL_STRUCT_FUNCTION (node->decl));
+
+      /* First do indirect call promotion and early inline to make the
+	 IR match the profiled binary before actual annotation.
+
+	 This is needed because an indirect call might have been promoted
+	 and inlined in the profiled binary. If we do not promote and
+	 inline these indirect calls before annotation, the profile for
+	 these promoted functions will be lost.
+
+	 e.g. foo() --indirect_call--> bar()
+	 In profiled binary, the callsite is promoted and inlined, making
+	 the profile look like:
+
+	 foo: {
+	   loc_foo_1: count_1
+	   bar@loc_foo_2: {
+	     loc_bar_1: count_2
+	     loc_bar_2: count_3
+	   }
+	 }
+
+	 Before AutoFDO pass, loc_foo_2 is not promoted thus not inlined.
+	 If we perform annotation on it, the profile inside bar@loc_foo2
+	 will be wasted.
+
+	 To avoid this, we promote loc_foo_2 and inline the promoted bar
+	 function before annotation, so the profile inside bar@loc_foo2
+	 will be useful.  */
+      autofdo::stmt_set promoted_stmts;
+      for (int i = 0; i < PARAM_VALUE (PARAM_EARLY_INLINER_MAX_ITERATIONS); i++)
+	{
+	  if (!flag_value_profile_transformations
+	      || !autofdo::afdo_vpt_for_early_inline (&promoted_stmts))
+	    break;
+	  early_inline ();
+	}
+
+      early_inline ();
+      autofdo::afdo_annotate_cfg (promoted_stmts);
+      compute_function_frequency ();
+      update_ssa (TODO_update_ssa);
+
+      /* Local pure-const may imply need to fixup the cfg.  */
+      if (execute_fixup_cfg () & TODO_cleanup_cfg)
+	cleanup_tree_cfg ();
+
+      free_dominance_info (CDI_DOMINATORS);
+      free_dominance_info (CDI_POST_DOMINATORS);
+      cgraph_edge::rebuild_edges ();
+      pop_cfun ();
+    }
+
+  return TODO_rebuild_cgraph_edges;
+}
+}  /* namespace autofdo.  */
+
+/* Read the profile from the profile data file.  */
+
+void
+read_autofdo_file (void)
+{
+  if (auto_profile_file == NULL)
+    auto_profile_file = DEFAULT_AUTO_PROFILE_FILE;
+
+  autofdo::afdo_profile_info = (struct gcov_ctr_summary *)
+      xcalloc (1, sizeof (struct gcov_ctr_summary));
+  autofdo::afdo_profile_info->runs = 1;
+  autofdo::afdo_profile_info->sum_max = 0;
+  autofdo::afdo_profile_info->sum_all = 0;
+
+  /* Read the profile from the profile file.  */
+  autofdo::read_profile ();
+}
+
+/* Free the resources.  */
+
+void
+end_auto_profile (void)
+{
+  delete autofdo::afdo_source_profile;
+  delete autofdo::afdo_string_table;
+  profile_info = NULL;
+}
+
+/* Returns TRUE if EDGE is hot enough to be inlined early.  */
+
+bool
+afdo_callsite_hot_enough_for_early_inline (struct cgraph_edge *edge)
+{
+  gcov_type count =
+      autofdo::afdo_source_profile->get_callsite_total_count (edge);
+  if (count > 0)
+    {
+      bool is_hot;
+      const struct gcov_ctr_summary *saved_profile_info = profile_info;
+      /* At earling inline stage, profile_info is not set yet. We need to
+	 temporarily set it to afdo_profile_info to calculate hotness.  */
+      profile_info = autofdo::afdo_profile_info;
+      is_hot = maybe_hot_count_p (NULL, count);
+      profile_info = saved_profile_info;
+      return is_hot;
+    }
+  else
+    return false;
+}
+
+namespace {
+
+const pass_data pass_data_ipa_auto_profile =
+{
+  SIMPLE_IPA_PASS,
+  "afdo", /* name */
+  OPTGROUP_NONE, /* optinfo_flags */
+  TV_IPA_AUTOFDO, /* tv_id */
+  0, /* properties_required */
+  0, /* properties_provided */
+  0, /* properties_destroyed */
+  0, /* todo_flags_start */
+  0, /* todo_flags_finish */
+};
+
+class pass_ipa_auto_profile : public simple_ipa_opt_pass
+{
+public:
+  pass_ipa_auto_profile(gcc::context *ctxt)
+    : simple_ipa_opt_pass(pass_data_ipa_auto_profile, ctxt)
+  {}
+
+  /* opt_pass methods: */
+  virtual bool gate (function *)
+    {
+      return flag_auto_profile;
+    }
+  virtual unsigned int execute (function *)
+    {
+      return autofdo::auto_profile ();
+    }
+}; // class pass_ipa_auto_profile
+
+} // anon namespace
+
+simple_ipa_opt_pass *
+make_pass_ipa_auto_profile (gcc::context *ctxt)
+{
+  return new pass_ipa_auto_profile (ctxt);
+}
+
Index: gcc/auto-profile.h
===================================================================
--- gcc/auto-profile.h	(revision 0)
+++ gcc/auto-profile.h	(revision 0)
@@ -0,0 +1,31 @@ 
+/* auto-profile.h - Defines data exported from auto-profile.c
+   Copyright (C) 2014. Free Software Foundation, Inc.
+   Contributed by Dehao Chen (dehao@google.com)
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef AUTO_PROFILE_H
+#define AUTO_PROFILE_H
+
+/* Read, process, finalize AutoFDO data structures.  */
+extern void read_autofdo_file (void);
+extern void end_auto_profile (void);
+
+/* Returns TRUE if EDGE is hot enough to be inlined early.  */
+extern bool afdo_callsite_hot_enough_for_early_inline (struct cgraph_edge *);
+
+#endif /* AUTO_PROFILE_H */
Index: gcc/cfgloop.c
===================================================================
--- gcc/cfgloop.c	(revision 215826)
+++ gcc/cfgloop.c	(working copy)
@@ -1802,7 +1802,7 @@ 
     }
   if (realistic
       && (!loop->any_estimate
-	  || wi::ltu_p (i_bound, loop->nb_iterations_estimate)))
+	  || (!flag_auto_profile && wi::ltu_p (i_bound, loop->nb_iterations_estimate))))
     {
       loop->any_estimate = true;
       loop->nb_iterations_estimate = i_bound;
Index: gcc/basic-block.h
===================================================================
--- gcc/basic-block.h	(revision 215826)
+++ gcc/basic-block.h	(working copy)
@@ -724,6 +724,7 @@ 
 extern void compute_available (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
 
 /* In predict.c */
+extern bool maybe_hot_count_p (struct function *, gcov_type);
 extern bool maybe_hot_bb_p (struct function *, const_basic_block);
 extern bool maybe_hot_edge_p (edge);
 extern bool probably_never_executed_bb_p (struct function *, const_basic_block);
Index: gcc/value-prof.c
===================================================================
--- gcc/value-prof.c	(revision 215826)
+++ gcc/value-prof.c	(working copy)
@@ -134,11 +134,10 @@ 
 static bool gimple_mod_pow2_value_transform (gimple_stmt_iterator *);
 static bool gimple_mod_subtract_transform (gimple_stmt_iterator *);
 static bool gimple_stringops_transform (gimple_stmt_iterator *);
-static bool gimple_ic_transform (gimple_stmt_iterator *);
 
 /* Allocate histogram value.  */
 
-static histogram_value
+histogram_value
 gimple_alloc_histogram_value (struct function *fun ATTRIBUTE_UNUSED,
 			      enum hist_type type, gimple stmt, tree value)
 {
@@ -1307,6 +1306,9 @@ 
 struct cgraph_node*
 find_func_by_profile_id (int profile_id)
 {
+  if (flag_auto_profile)
+    return cgraph_node::get_for_asmname (
+	get_identifier ((const char *)(size_t)profile_id));
   cgraph_node **val = cgraph_node_map->get (profile_id);
   if (val)
     return *val;
@@ -1320,7 +1322,7 @@ 
    may ICE. Here we only do very minimal sanity check just to make compiler happy.
    Returns true if TARGET is considered ok for call CALL_STMT.  */
 
-static bool
+bool
 check_ic_target (gimple call_stmt, struct cgraph_node *target)
 {
    location_t locus;
@@ -1483,7 +1485,7 @@ 
   this call to:
  */
 
-static bool
+bool
 gimple_ic_transform (gimple_stmt_iterator *gsi)
 {
   gimple stmt = gsi_stmt (*gsi);
Index: gcc/value-prof.h
===================================================================
--- gcc/value-prof.h	(revision 215826)
+++ gcc/value-prof.h	(working copy)
@@ -75,6 +75,8 @@ 
 extern void gimple_find_values_to_profile (histogram_values *);
 extern bool gimple_value_profile_transformations (void);
 
+histogram_value gimple_alloc_histogram_value (struct function *, enum hist_type,
+					      gimple stmt, tree);
 histogram_value gimple_histogram_value (struct function *, gimple);
 histogram_value gimple_histogram_value_of_type (struct function *, gimple,
 						enum hist_type);
@@ -89,6 +91,8 @@ 
 void free_histograms (void);
 void stringop_block_profile (gimple, unsigned int *, HOST_WIDE_INT *);
 gimple gimple_ic (gimple, struct cgraph_node *, int, gcov_type, gcov_type);
+bool check_ic_target (gimple, struct cgraph_node *);
+bool gimple_ic_transform (gimple_stmt_iterator *);
 
 
 /* In tree-profile.c.  */
Index: gcc/coverage.c
===================================================================
--- gcc/coverage.c	(revision 215826)
+++ gcc/coverage.c	(working copy)
@@ -55,6 +55,7 @@ 
 #include "filenames.h"
 #include "target.h"
 #include "params.h"
+#include "auto-profile.h"
 
 #include "gcov-io.h"
 #include "gcov-io.c"
@@ -1208,7 +1209,9 @@ 
 
   bbg_file_stamp = local_tick;
   
-  if (flag_branch_probabilities)
+  if (flag_auto_profile)
+    read_autofdo_file ();
+  else if (flag_branch_probabilities)
     read_counts_file ();
 
   /* Name of bbg file.  */
Index: gcc/timevar.def
===================================================================
--- gcc/timevar.def	(revision 215826)
+++ gcc/timevar.def	(working copy)
@@ -89,6 +89,7 @@ 
 DEFTIMEVAR (TV_WHOPR_LTRANS          , "whopr ltrans")
 DEFTIMEVAR (TV_IPA_REFERENCE         , "ipa reference")
 DEFTIMEVAR (TV_IPA_PROFILE           , "ipa profile")
+DEFTIMEVAR (TV_IPA_AUTOFDO           , "auto profile")
 DEFTIMEVAR (TV_IPA_PURE_CONST        , "ipa pure const")
 DEFTIMEVAR (TV_IPA_PTA               , "ipa points-to")
 DEFTIMEVAR (TV_IPA_SRA               , "ipa SRA")
Index: gcc/common.opt
===================================================================
--- gcc/common.opt	(revision 215826)
+++ gcc/common.opt	(working copy)
@@ -895,6 +895,16 @@ 
 Common Report Var(flag_auto_inc_dec) Init(1)
 Generate auto-inc/dec instructions
 
+fauto-profile
+Common Report Var(flag_auto_profile) Optimization
+Use sample profile information for call graph node weights. The default
+profile file is fbdata.afdo in 'pwd'.
+
+fauto-profile=
+Common Joined RejectNegative Var(auto_profile_file)
+Use sample profile information for call graph node weights. The profile
+file is specified in the argument.
+
 ; -fcheck-bounds causes gcc to generate array bounds checks.
 ; For C, C++ and ObjC: defaults off.
 ; For Java: defaults to on.
Index: gcc/toplev.c
===================================================================
--- gcc/toplev.c	(revision 215826)
+++ gcc/toplev.c	(working copy)
@@ -79,6 +79,7 @@ 
 #include "diagnostic-color.h"
 #include "context.h"
 #include "pass_manager.h"
+#include "auto-profile.h"
 #include "optabs.h"
 
 #if defined(DBX_DEBUGGING_INFO) || defined(XCOFF_DEBUGGING_INFO)
@@ -663,6 +664,10 @@ 
       targetm.asm_out.output_ident (ident_str);
     }
 
+  /* Auto profile finalization. */
+  if (flag_auto_profile)
+    end_auto_profile ();
+
   /* Invoke registered plugin callbacks.  */
   invoke_plugin_callbacks (PLUGIN_FINISH_UNIT, NULL);
 
Index: gcc/tree-profile.c
===================================================================
--- gcc/tree-profile.c	(revision 215826)
+++ gcc/tree-profile.c	(working copy)
@@ -699,8 +699,10 @@ 
 bool
 pass_ipa_tree_profile::gate (function *)
 {
-  /* When profile instrumentation, use or test coverage shall be performed.  */
-  return (!in_lto_p
+  /* When profile instrumentation, use or test coverage shall be performed.
+     But for AutoFDO, this there is no instrumentation, thus this pass is
+     diabled.  */
+  return (!in_lto_p && !flag_auto_profile
 	  && (flag_branch_probabilities || flag_test_coverage
 	      || profile_arc_flag));
 }
Index: gcc/ipa-inline.c
===================================================================
--- gcc/ipa-inline.c	(revision 215826)
+++ gcc/ipa-inline.c	(working copy)
@@ -121,6 +121,7 @@ 
 #include "ipa-inline.h"
 #include "ipa-utils.h"
 #include "sreal.h"
+#include "auto-profile.h"
 #include "cilk.h"
 #include "builtins.h"
 
@@ -449,6 +450,14 @@ 
 
   if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
     ;
+  /* For AutoFDO, we need to make sure that before profile annotation, all
+     hot paths' IR look exactly the same as profiled binary. As a result,
+     in einliner, we will disregard size limit and inline those callsites
+     that are:
+       * inlined in the profiled binary, and
+       * the cloned callee has enough samples to be considered "hot".  */
+  else if (flag_auto_profile && afdo_callsite_hot_enough_for_early_inline (e))
+    ;
   else if (!DECL_DECLARED_INLINE_P (callee->decl)
 	   && !flag_inline_small_functions)
     {
@@ -2366,39 +2375,8 @@ 
   return inlined;
 }
 
-/* Do inlining of small functions.  Doing so early helps profiling and other
-   passes to be somewhat more effective and avoids some code duplication in
-   later real inlining pass for testcases with very many function calls.  */
-
-namespace {
-
-const pass_data pass_data_early_inline =
-{
-  GIMPLE_PASS, /* type */
-  "einline", /* name */
-  OPTGROUP_INLINE, /* optinfo_flags */
-  TV_EARLY_INLINING, /* tv_id */
-  PROP_ssa, /* properties_required */
-  0, /* properties_provided */
-  0, /* properties_destroyed */
-  0, /* todo_flags_start */
-  0, /* todo_flags_finish */
-};
-
-class pass_early_inline : public gimple_opt_pass
-{
-public:
-  pass_early_inline (gcc::context *ctxt)
-    : gimple_opt_pass (pass_data_early_inline, ctxt)
-  {}
-
-  /* opt_pass methods: */
-  virtual unsigned int execute (function *);
-
-}; // class pass_early_inline
-
 unsigned int
-pass_early_inline::execute (function *fun)
+early_inliner (function *fun)
 {
   struct cgraph_node *node = cgraph_node::get (current_function_decl);
   struct cgraph_edge *edge;
@@ -2499,6 +2477,43 @@ 
   return todo;
 }
 
+/* Do inlining of small functions.  Doing so early helps profiling and other
+   passes to be somewhat more effective and avoids some code duplication in
+   later real inlining pass for testcases with very many function calls.  */
+
+namespace {
+
+const pass_data pass_data_early_inline =
+{
+  GIMPLE_PASS, /* type */
+  "einline", /* name */
+  OPTGROUP_INLINE, /* optinfo_flags */
+  TV_EARLY_INLINING, /* tv_id */
+  PROP_ssa, /* properties_required */
+  0, /* properties_provided */
+  0, /* properties_destroyed */
+  0, /* todo_flags_start */
+  0, /* todo_flags_finish */
+};
+
+class pass_early_inline : public gimple_opt_pass
+{
+public:
+  pass_early_inline (gcc::context *ctxt)
+    : gimple_opt_pass (pass_data_early_inline, ctxt)
+  {}
+
+  /* opt_pass methods: */
+  virtual unsigned int execute (function *);
+
+}; // class pass_early_inline
+
+unsigned int
+pass_early_inline::execute (function *fun)
+{
+  return early_inliner (fun);
+}
+
 } // anon namespace
 
 gimple_opt_pass *
Index: gcc/ipa-inline.h
===================================================================
--- gcc/ipa-inline.h	(revision 215826)
+++ gcc/ipa-inline.h	(working copy)
@@ -238,6 +238,7 @@ 
 void free_growth_caches (void);
 void compute_inline_parameters (struct cgraph_node *, bool);
 bool speculation_useful_p (struct cgraph_edge *e, bool anticipate_inlining);
+unsigned int early_inliner (function *fun);
 
 /* In ipa-inline-transform.c  */
 bool inline_call (struct cgraph_edge *, bool, vec<cgraph_edge *> *, int *, bool,
Index: gcc/tree-ssa-live.c
===================================================================
--- gcc/tree-ssa-live.c	(revision 215826)
+++ gcc/tree-ssa-live.c	(working copy)
@@ -605,7 +605,7 @@ 
      ;
    /* When not generating debug info we can eliminate info on unused
       variables.  */
-   else if (debug_info_level == DINFO_LEVEL_NONE)
+   else if (!flag_auto_profile && debug_info_level == DINFO_LEVEL_NONE)
      {
        /* Even for -g0 don't prune outer scopes from artificial
 	  functions, otherwise diagnostics using tree_nonartificial_location
Index: gcc/gcov-io.h
===================================================================
--- gcc/gcov-io.h	(revision 215826)
+++ gcc/gcov-io.h	(working copy)
@@ -244,6 +244,9 @@ 
 #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000)
 #define GCOV_TAG_SUMMARY_LENGTH(NUM)  \
         (1 + GCOV_COUNTERS_SUMMABLE * (10 + 3 * 2) + (NUM) * 5)
+#define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000)
+#define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000)
+#define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000)
 
 
 /* Counters that are collected.  */
Index: gcc/Makefile.in
===================================================================
--- gcc/Makefile.in	(revision 215826)
+++ gcc/Makefile.in	(working copy)
@@ -1153,6 +1153,7 @@ 
 	alias.o \
 	alloc-pool.o \
 	auto-inc-dec.o \
+	auto-profile.o \
 	bb-reorder.o \
 	bitmap.o \
 	bt-load.o \
Index: gcc/predict.c
===================================================================
--- gcc/predict.c	(revision 215826)
+++ gcc/predict.c	(working copy)
@@ -161,7 +161,7 @@ 
 
 /* Return TRUE if frequency FREQ is considered to be hot.  */
 
-static inline bool
+bool
 maybe_hot_count_p (struct function *fun, gcov_type count)
 {
   if (fun && profile_status_for_fn (fun) != PROFILE_READ)
@@ -2852,7 +2852,7 @@ 
   /* Don't overwrite the estimated frequencies when the profile for
      the function is missing.  We may drop this function PROFILE_GUESSED
      later in drop_profile ().  */
-  if (!ENTRY_BLOCK_PTR_FOR_FN (cfun)->count)
+  if (!flag_auto_profile && !ENTRY_BLOCK_PTR_FOR_FN (cfun)->count)
     return 0;
 
   FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), NULL, next_bb)
@@ -3223,7 +3223,8 @@ 
     count_max = MAX (bb->count, count_max);
 
   if (profile_status_for_fn (cfun) == PROFILE_GUESSED
-      || (profile_status_for_fn (cfun) == PROFILE_READ && count_max < REG_BR_PROB_BASE/10))
+      || (!flag_auto_profile && profile_status_for_fn (cfun) == PROFILE_READ
+	  && count_max < REG_BR_PROB_BASE/10))
     {
       loop_optimizer_init (0);
       add_noreturn_fake_exit_edges ();
Index: gcc/doc/invoke.texi
===================================================================
--- gcc/doc/invoke.texi	(revision 215826)
+++ gcc/doc/invoke.texi	(working copy)
@@ -365,7 +365,8 @@ 
 @gccoptlist{-faggressive-loop-optimizations -falign-functions[=@var{n}] @gol
 -falign-jumps[=@var{n}] @gol
 -falign-labels[=@var{n}] -falign-loops[=@var{n}] @gol
--fassociative-math -fauto-inc-dec -fbranch-probabilities @gol
+-fassociative-math -fauto-profile -fauto-profile[=@var{path}] @gol
+-fauto-inc-dec -fbranch-probabilities @gol
 -fbranch-target-load-optimize -fbranch-target-load-optimize2 @gol
 -fbtr-bb-exclusive -fcaller-saves @gol
 -fcheck-data-deps -fcombine-stack-adjustments -fconserve-stack @gol
@@ -9164,6 +9165,19 @@ 
 
 If @var{path} is specified, GCC looks at the @var{path} to find
 the profile feedback data files. See @option{-fprofile-dir}.
+
+@item -fauto-profile
+@itemx -fauto-profile=@var{path}
+@opindex fauto-profile
+Enable sampling based feedback directed optimizations, and optimizations
+generally profitable only with profile feedback available.
+
+The following options are enabled: @code{-fbranch-probabilities}, @code{-fvpt},
+@code{-funroll-loops}, @code{-fpeel-loops}, @code{-ftracer}, @code{-ftree-vectorize},
+@code{ftree-loop-distribute-patterns}
+
+If @var{path} is specified, GCC looks at the @var{path} to find
+the profile feedback data files.
 @end table
 
 The following options control compiler behavior regarding floating-point 
Index: gcc/profile.c
===================================================================
--- gcc/profile.c	(revision 215826)
+++ gcc/profile.c	(working copy)
@@ -106,6 +106,14 @@ 
 static int total_hist_br_prob[20];
 static int total_num_branches;
 
+/* Helper function to update gcov_working_sets.  */
+
+void add_working_set (gcov_working_set_t *set) {
+  int i = 0;
+  for (; i < NUM_GCOV_WORKING_SETS; i++)
+    gcov_working_sets[i] = set[i];
+}
+
 /* Forward declarations.  */
 static void find_spanning_tree (struct edge_list *);
 
Index: gcc/profile.h
===================================================================
--- gcc/profile.h	(revision 215826)
+++ gcc/profile.h	(working copy)
@@ -47,6 +47,7 @@ 
 extern void del_node_map (void);
 
 extern void get_working_sets (void);
+extern void add_working_set (gcov_working_set_t *);
 
 /* In predict.c.  */
 extern gcov_type get_hot_bb_threshold (void);
Index: gcc/passes.def
===================================================================
--- gcc/passes.def	(revision 215826)
+++ gcc/passes.def	(working copy)
@@ -90,6 +90,7 @@ 
       NEXT_PASS (pass_rebuild_cgraph_edges);
       NEXT_PASS (pass_inline_parameters);
   POP_INSERT_PASSES ()
+  NEXT_PASS (pass_ipa_auto_profile);
   NEXT_PASS (pass_ipa_free_inline_summary);
   NEXT_PASS (pass_ipa_tree_profile);
   PUSH_INSERT_PASSES_WITHIN (pass_ipa_tree_profile)
Index: gcc/tree-pass.h
===================================================================
--- gcc/tree-pass.h	(revision 215826)
+++ gcc/tree-pass.h	(working copy)
@@ -449,6 +449,7 @@ 
 extern simple_ipa_opt_pass
 							      *make_pass_ipa_function_and_variable_visibility (gcc::context *ctxt);
 extern simple_ipa_opt_pass *make_pass_ipa_tree_profile (gcc::context *ctxt);
+extern simple_ipa_opt_pass *make_pass_ipa_auto_profile (gcc::context *ctxt);
 
 extern simple_ipa_opt_pass *make_pass_early_local_passes (gcc::context *ctxt);
 
Index: gcc/opts.c
===================================================================
--- gcc/opts.c	(revision 215826)
+++ gcc/opts.c	(working copy)
@@ -1279,6 +1279,55 @@ 
 		       opts->x_help_columns, opts, lang_mask);
 }
 
+static void
+enable_fdo_optimizations (struct gcc_options *opts,
+			  struct gcc_options *opts_set,
+			  int value)
+{
+  if (!opts_set->x_flag_branch_probabilities)
+    opts->x_flag_branch_probabilities = value;
+  if (!opts_set->x_flag_profile_values)
+    opts->x_flag_profile_values = value;
+  if (!opts_set->x_flag_unroll_loops)
+    opts->x_flag_unroll_loops = value;
+  if (!opts_set->x_flag_peel_loops)
+    opts->x_flag_peel_loops = value;
+  if (!opts_set->x_flag_tracer)
+    opts->x_flag_tracer = value;
+  if (!opts_set->x_flag_value_profile_transformations)
+    opts->x_flag_value_profile_transformations = value;
+  if (!opts_set->x_flag_inline_functions)
+    opts->x_flag_inline_functions = value;
+  if (!opts_set->x_flag_ipa_cp)
+    opts->x_flag_ipa_cp = value;
+  if (!opts_set->x_flag_ipa_cp_clone
+      && value && opts->x_flag_ipa_cp)
+    opts->x_flag_ipa_cp_clone = value;
+  if (!opts_set->x_flag_predictive_commoning)
+    opts->x_flag_predictive_commoning = value;
+  if (!opts_set->x_flag_unswitch_loops)
+    opts->x_flag_unswitch_loops = value;
+  if (!opts_set->x_flag_gcse_after_reload)
+    opts->x_flag_gcse_after_reload = value;
+  if (!opts_set->x_flag_tree_loop_vectorize
+      && !opts_set->x_flag_tree_vectorize)
+    opts->x_flag_tree_loop_vectorize = value;
+  if (!opts_set->x_flag_tree_slp_vectorize
+      && !opts_set->x_flag_tree_vectorize)
+    opts->x_flag_tree_slp_vectorize = value;
+  if (!opts_set->x_flag_vect_cost_model)
+    opts->x_flag_vect_cost_model = VECT_COST_MODEL_DYNAMIC;
+  if (!opts_set->x_flag_tree_loop_distribute_patterns)
+    opts->x_flag_tree_loop_distribute_patterns = value;
+  if (!opts_set->x_flag_profile_reorder_functions)
+    opts->x_flag_profile_reorder_functions = value;
+  /* Indirect call profiling should do all useful transformations
+     speculative devirtualization does.  */
+  if (!opts_set->x_flag_devirtualize_speculatively
+      && opts->x_flag_value_profile_transformations)
+    opts->x_flag_devirtualize_speculatively = false;
+}
+
 /* Handle target- and language-independent options.  Return zero to
    generate an "unknown option" message.  Only options that need
    extra handling need to be listed here; if you simply want
@@ -1746,50 +1795,23 @@ 
       value = true;
       /* No break here - do -fprofile-use processing. */
     case OPT_fprofile_use:
-      if (!opts_set->x_flag_branch_probabilities)
-	opts->x_flag_branch_probabilities = value;
-      if (!opts_set->x_flag_profile_values)
-	opts->x_flag_profile_values = value;
-      if (!opts_set->x_flag_unroll_loops)
-	opts->x_flag_unroll_loops = value;
-      if (!opts_set->x_flag_peel_loops)
-	opts->x_flag_peel_loops = value;
-      if (!opts_set->x_flag_tracer)
-	opts->x_flag_tracer = value;
-      if (!opts_set->x_flag_value_profile_transformations)
-	opts->x_flag_value_profile_transformations = value;
-      if (!opts_set->x_flag_inline_functions)
-	opts->x_flag_inline_functions = value;
-      if (!opts_set->x_flag_ipa_cp)
-	opts->x_flag_ipa_cp = value;
-      if (!opts_set->x_flag_ipa_cp_clone
-	  && value && opts->x_flag_ipa_cp)
-	opts->x_flag_ipa_cp_clone = value;
-      if (!opts_set->x_flag_predictive_commoning)
-	opts->x_flag_predictive_commoning = value;
-      if (!opts_set->x_flag_unswitch_loops)
-	opts->x_flag_unswitch_loops = value;
-      if (!opts_set->x_flag_gcse_after_reload)
-	opts->x_flag_gcse_after_reload = value;
-      if (!opts_set->x_flag_tree_loop_vectorize
-          && !opts_set->x_flag_tree_vectorize)
-	opts->x_flag_tree_loop_vectorize = value;
-      if (!opts_set->x_flag_tree_slp_vectorize
-          && !opts_set->x_flag_tree_vectorize)
-	opts->x_flag_tree_slp_vectorize = value;
-      if (!opts_set->x_flag_vect_cost_model)
-	opts->x_flag_vect_cost_model = VECT_COST_MODEL_DYNAMIC;
-      if (!opts_set->x_flag_tree_loop_distribute_patterns)
-	opts->x_flag_tree_loop_distribute_patterns = value;
-      if (!opts_set->x_flag_profile_reorder_functions)
-	opts->x_flag_profile_reorder_functions = value;
-      /* Indirect call profiling should do all useful transformations
- 	 speculative devirtualization does.  */
-      if (!opts_set->x_flag_devirtualize_speculatively
-	  && opts->x_flag_value_profile_transformations)
-	opts->x_flag_devirtualize_speculatively = false;
+      enable_fdo_optimizations (opts, opts_set, value);
       break;
 
+    case OPT_fauto_profile_:
+      opts->x_auto_profile_file = xstrdup (arg);
+      opts->x_flag_auto_profile = true;
+      value = true;
+      /* No break here - do -fauto-profile processing. */
+    case OPT_fauto_profile:
+      enable_fdo_optimizations (opts, opts_set, value);
+      if (!opts_set->x_flag_profile_correction)
+	opts->x_flag_profile_correction = value;
+      maybe_set_param_value (
+	PARAM_EARLY_INLINER_MAX_ITERATIONS, 10,
+	opts->x_param_values, opts_set->x_param_values);
+      break;
+
     case OPT_fprofile_generate_:
       opts->x_profile_data_prefix = xstrdup (arg);
       value = true;